When discussing study results with a patient who is considering a treatment, which limitations should you emphasize?

• A. That there are no limitations.
• B. Sample size, generalizability, biases, and how these affect applicability.
• C. Only the statistical methods used.
• D. That all results apply perfectly to any patient.

Answer: (B)

The main idea is that study results come with limits that shape how much we can apply them to a specific patient. When you’re discussing treatment options, it’s crucial to highlight how confident we are in the findings and whether they would translate to the patient you’re treating.

First, sample size matters because a smaller group provides less precise estimates of benefit or harm. With fewer participants, the observed effect could be due to chance, and the confidence interval around that effect is wider. That means we should be more cautious about expecting the same benefit in a real-world patient.

Second, generalizability, or external validity, asks whether the people in the study resemble the patient in important ways—age, sex, other health conditions, disease severity, and how the treatment was used. If the study population isn’t similar to the patient, the results may not apply as well to them.

Third, biases can distort study findings. Selection bias, measurement bias, and confounding can skew estimates of efficacy or safety, making the treatment seem better or worse than it truly is. Recognizing these biases helps you understand the real uncertainty behind the reported outcomes.

Because of these factors, you should discuss how they affect whether the results are relevant to the patient, how certain we are about the expected benefits and risks, and whether additional evidence or a targeted approach is warranted. This is why simply stating the results isn’t enough—you need to connect them to the patient’s situation and the uncertainties involved.

Other choices fall short because they ignore limitations, focus only on statistical methods, or assume results apply to everyone without exception.